A brief history of the United States Medicare health insurance program is provided, with a description of each of its parts. The history of the Medicare spending program is outlined, along with the history of the programs funding. Future spending projections for the Medicare program and key factors driving future spending are identified, along with other factors that may affect the future level of program spending that are not currently accounted for in official projections. New lessons learned from the national experiment to provide Medicare beneficiaries with a direct economic stake for lowering the overall cost of the program via the new Medicare Part D prescription drug coverage program may provide the key to bringing the growth of Medicare spending to sustainable levels through the implementation similar reforms to Medicares core health insurance programs. Additionally, more closely linking the programs expenditures to its actual revenues may ensure its fiscal viability.